/*******************************************************************************
 * Copyright (c) 2000, 2005 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package com.architexa.org.eclipse.gef.tools;

import com.architexa.org.eclipse.draw2d.AbstractBorder;
import com.architexa.org.eclipse.draw2d.AncestorListener;
import com.architexa.org.eclipse.draw2d.Border;
import com.architexa.org.eclipse.draw2d.ColorConstants;
import com.architexa.org.eclipse.draw2d.Figure;
import com.architexa.org.eclipse.draw2d.Graphics;
import com.architexa.org.eclipse.draw2d.IFigure;
import com.architexa.org.eclipse.draw2d.geometry.Insets;
import com.architexa.org.eclipse.draw2d.geometry.Rectangle;
import com.architexa.org.eclipse.gef.EditPart;
import com.architexa.org.eclipse.gef.EditPartListener;
import com.architexa.org.eclipse.gef.GraphicalEditPart;
import com.architexa.org.eclipse.gef.LayerConstants;
import com.architexa.org.eclipse.gef.commands.Command;
import com.architexa.org.eclipse.gef.commands.CommandStack;
import com.architexa.org.eclipse.gef.editparts.LayerManager;
import com.architexa.org.eclipse.gef.requests.DirectEditRequest;

import java.lang.reflect.Constructor;

import org.eclipse.swt.events.ControlAdapter;
import org.eclipse.swt.events.ControlEvent;
import org.eclipse.swt.events.ControlListener;
import org.eclipse.swt.events.VerifyListener;
import org.eclipse.swt.graphics.Color;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Display;

import org.eclipse.jface.viewers.CellEditor;
import org.eclipse.jface.viewers.ICellEditorListener;



/**
 * Manages the direct edit operation by creating and maintaining the 
 * {@link org.eclipse.jface.viewers.CellEditor} and executing the resulting command if 
 * the cell editor value has changed.
 */
public abstract class DirectEditManager {

private static final Color BLUE = ColorConstants.menuBackgroundSelected;
private static final Border BORDER_FRAME = new DirectEditBorder();

private AncestorListener ancestorListener;
private EditPartListener editPartListener;
private ControlListener controlListener;
private IFigure cellEditorFrame;
private ICellEditorListener cellEditorListener;
private boolean showingFeedback;
private boolean dirty;
private DirectEditRequest request;
private CellEditorLocator locator;
private GraphicalEditPart source;
private CellEditor ce;
private Class editorType;
private boolean committing = false;
private Object feature;

/**
 * Constructs a new DirectEditManager for the given source edit part. The cell editor 
 * will be created by instantiating the type <i>editorType</i>. The cell editor will be 
 * placed using the given CellEditorLocator.
 * 
 * @param source the source edit part
 * @param editorType the cell editor type
 * @param locator the locator
 */
public DirectEditManager(GraphicalEditPart source, Class editorType, 
		CellEditorLocator locator) {
	this.source = source;
	this.locator = locator;
	this.editorType = editorType;
}

/**
 * Constructs a new DirectEditManager for the given source edit part. The cell editor 
 * will be created by instantiating the type <i>editorType</i>. The cell editor will be 
 * placed using the given CellEditorLocator.
 * 
 * @param source the source edit part
 * @param editorType the cell editor type
 * @param locator the locator
 * @param feature If the EditPart supports direct editing of multiple features, this parameter can be
 * used to discriminate among them.
 * @since 3.2
 */
public DirectEditManager(GraphicalEditPart source, Class editorType, 
		CellEditorLocator locator, Object feature) {
	this(source, editorType, locator );
	this.feature = feature;
}

/**
 * Cleanup is done here.  Any feedback is erased and listeners unhooked.  If the cell
 * editor is not <code>null</code>, it will be {@link CellEditor#deactivate() deativated},
 * {@link CellEditor#dispose() disposed}, and set to <code>null</code>.
 */
protected void bringDown() {
	eraseFeedback();
	unhookListeners();
	if (getCellEditor() != null) {
		getCellEditor().deactivate();
		getCellEditor().dispose();
		setCellEditor(null);
	}
	request = null;
	dirty = false;
}

/**
 * Commits the current value of the cell editor by getting a {@link Command} from the 
 * source edit part and executing it via the {@link CommandStack}.  Finally, 
 * {@link #bringDown()} is called to perform and necessary cleanup.
 */
protected void commit() {
	if (committing)
		return;
	committing = true;
	try {
		eraseFeedback();
		if (isDirty()) {
			CommandStack stack = 
					getEditPart().getViewer().getEditDomain().getCommandStack();
			stack.execute(getEditPart().getCommand(getDirectEditRequest()));
		}
	} finally {
		bringDown();
		committing = false;
	}
}

/**
 * Creates the cell editor on the given composite.  The cell editor is created by 
 * instantiating the cell editor type passed into this DirectEditManager's constuctor.
 * @param composite the composite to create the cell editor on
 * @return the newly created cell editor
 */
protected CellEditor createCellEditorOn(Composite composite) {
	try {
		Constructor constructor = editorType.getConstructor(new Class[]{Composite.class});
		return (CellEditor)constructor.newInstance(new Object[]{composite});
	} catch (Exception e) {
		return null;
	}
}

/**
 * Creates and returns the DirectEditRequest.
 * @return the direct edit request
 */
protected DirectEditRequest createDirectEditRequest() {
	DirectEditRequest req = new DirectEditRequest();
	req.setCellEditor(getCellEditor());
	req.setDirectEditFeature(getDirectEditFeature());
	return req;
}

/**
 * Asks the source edit part to erase source feedback.
 */
protected void eraseFeedback() {
	if (showingFeedback) {
		LayerManager.Helper.find(getEditPart()).
			getLayer(LayerConstants.FEEDBACK_LAYER).
			remove(getCellEditorFrame());
		cellEditorFrame = null;
		getEditPart().eraseSourceFeedback(getDirectEditRequest());
		showingFeedback = false;
	}
}

/**
 * Returns the cell editor.
 * @return the cell editor
 */
protected CellEditor getCellEditor() {
	return ce;
}

private IFigure getCellEditorFrame() {
	if (cellEditorFrame != null)
		return cellEditorFrame;
	cellEditorFrame = new Figure();
	cellEditorFrame.setBorder(BORDER_FRAME);
	return cellEditorFrame;
}

private Control getControl() {
	return ce.getControl();
}

/**
 * @return <code>Object</code> that can be used if the EditPart supports direct editing of multiple 
 * features, this parameter can be used to discriminate among them.
 * @since 3.2
 */
protected Object getDirectEditFeature() {
	return feature;
}

/**
 * Returns the direct edit request, creating it if needed.
 * @return the direct edit request
 */
protected DirectEditRequest getDirectEditRequest() {
	if (request == null)
		request = createDirectEditRequest();
	return request;
}

/**
 * Returns the source edit part.
 * @return the source edit part
 */
protected GraphicalEditPart getEditPart() {
	return source;
}

private CellEditorLocator getLocator() {
	return locator;
}

private void handleValueChanged() {
	setDirty(true);
	showFeedback();
	placeCellEditor();
}

private void hookListeners() {
	ancestorListener = new AncestorListener.Stub() {
		public void ancestorMoved(IFigure ancestor) {
			placeCellEditor();
		}
	};
	getEditPart().getFigure().addAncestorListener(ancestorListener);

	Control control = getControl(); 	
	
	controlListener = new ControlAdapter() {
		public void controlMoved(ControlEvent e) {
			// This must be handled async because during scrolling, the CellEditor moves 
			// first, but then afterwards the viewport Scrolls, which would cause the 
			// shadow to move twice
			Display.getCurrent().asyncExec(new Runnable() {
				public void run() {
					placeBorder();
				}
			});
		}
		public void controlResized(ControlEvent e) {
			placeBorder();
		}
	};
	control.addControlListener(controlListener);

	cellEditorListener = new ICellEditorListener() {
		public void applyEditorValue() {
			commit();
		}
		public void cancelEditor() {
			bringDown();
		}
		public void editorValueChanged(boolean old, boolean newState) {
			handleValueChanged();
		}
	};
	getCellEditor().addListener(cellEditorListener);
	
	editPartListener = new EditPartListener.Stub () {
		public void partDeactivated(EditPart editpart) {
			bringDown();
		}
	};
	getEditPart().addEditPartListener(editPartListener);
}

/**
 * Initializes the cell editor.  Subclasses should implement this to set the initial text 
 * and add things such as {@link VerifyListener VerifyListeners}, if needed.
 */
protected abstract void initCellEditor();

/**
 * Returns <code>true</code> if the cell editor's value has been changed.
 * @return <code>true</code> if the cell editor is dirty
 */
protected boolean isDirty() {
	return dirty;
}

private void placeBorder() {
	if (showingFeedback) {
		IFigure shadow = getCellEditorFrame();
		Rectangle rect = new Rectangle(getCellEditor().getControl().getBounds());
		rect.expand(shadow.getInsets());
		shadow.translateToRelative(rect);
		shadow.setBounds(rect);
	}
}

private void placeCellEditor() {
	getLocator().relocate(getCellEditor());
}

/**
 * Sets the cell editor to the given editor.
 * @param editor the cell editor
 */
protected void setCellEditor(CellEditor editor) {
	ce = editor;
	if (ce == null)
		return;
	hookListeners();
}

/**
 * Sets the dirty property.
 * @param value the dirty property
 */
protected void setDirty(boolean value) {
	dirty = value;
}

/**
 * Sets the source edit part.
 * @param source the source edit part
 */
protected void setEditPart(GraphicalEditPart source) {
	this.source = source;
//	source.addEditPartListener();
}

/**
 * Sets the CellEditorLocator used to place the cell editor in the correct location.
 * @param locator the locator
 */
public void setLocator(CellEditorLocator locator) {
	this.locator = locator;
}

/**
 * Shows the cell editor when direct edit is started.  Calls {@link #initCellEditor()},
 * {@link CellEditor#activate()}, and {@link #showFeedback()}.
 */
public void show() {
	if (getCellEditor() != null)
		return;
	Composite composite = (Composite)source.getViewer().getControl();
	setCellEditor(createCellEditorOn(composite));
	if (getCellEditor() == null)
		return;
	initCellEditor();
	getCellEditor().activate();
	placeCellEditor();
	getControl().setVisible(true);
	getCellEditor().setFocus();
	showFeedback();
}

private void showCellEditorFrame() {
	LayerManager.Helper.find(getEditPart()).
		getLayer(LayerConstants.FEEDBACK_LAYER).
		add(getCellEditorFrame());
	placeBorder();
}

/**
 * Asks the source edit part to show source feedback.
 */
public void showFeedback() {
	if (!showingFeedback)
		showCellEditorFrame();
	showingFeedback = true;
	showCellEditorFrame();
	getEditPart().showSourceFeedback(getDirectEditRequest());
}

/**
 * Unhooks listeners.  Called from {@link #bringDown()}.
 * TODO: hookListeners() and unhookListeners() should have the same visibility.
 */
protected void unhookListeners() {
	getEditPart().getFigure().removeAncestorListener(ancestorListener);
	getEditPart().removeEditPartListener(editPartListener);
	ancestorListener = null;
	editPartListener = null;
	
	if (getCellEditor() == null)
		return;
	getCellEditor().removeListener(cellEditorListener);
	cellEditorListener = null;

	Control control = getCellEditor().getControl();
	if (control == null || control.isDisposed())
		return;
	control.removeControlListener(controlListener);
	controlListener = null;
}

private static class DirectEditBorder
	extends AbstractBorder
{
	private static final Insets insets = new Insets(1, 2, 2, 2);
	public Insets getInsets(IFigure figure) {
		return insets;
	}

	public void paint(IFigure figure, Graphics graphics, Insets insets) {
		Rectangle rect = getPaintRectangle(figure, insets);
		graphics.setForegroundColor(ColorConstants.white);
		graphics.drawLine(rect.x, rect.y, rect.x, rect.bottom());
		rect.x++;
		rect.width--;
		rect.resize(-1, -1);
		graphics.setForegroundColor(ColorConstants.black);
		graphics.drawLine(rect.x + 2, rect.bottom(), rect.right(), rect.bottom());
		graphics.drawLine(rect.right(), rect.bottom(), rect.right(), rect.y + 2);

		rect.resize(-1, -1);
		graphics.setForegroundColor(BLUE);
		graphics.drawRectangle(rect);
	}
}

}
